function array2xml($array, $tag) {

    function ia2xml($array) {
        $xml="";
        foreach ($array as $key=>$value) {
            if (is_array($value)) {
                $xml.="<$key>".ia2xml($value)."</$key>";
            } else {
                $xml.="<$key>".$value."</$key>";
            }
        }
        return $xml;
    }

    return simplexml_load_string("<$tag>".ia2xml($array)."</$tag>");
}

$test['type']='lunch';
$test['time']='12:30';
$test['menu']=array('entree'=>'salad', 'maincourse'=>'steak');

echo array2xml($test,"meal")->asXML();